The phrase "tense negotiations" refers to a situation where people are having important discussions that are filled with stress, unease, or anxiety. Full definition
How do you keep the peace between buyers and sellers in today's often tense negotiations? (realtormag.realtor.org)
Since the June 22 Yulin dog meat festival, members of China Animal Protection Power have rescued more than 1,000 dogs bound for slaughter in a series of dog truck interceptions on China's highways involving days of tense negotiation with dog traders and police. (hsi.org)
During tense negotiations over the bonds late last year, the city said the state threatened to zero out the fall funding entirely — a charge the governor's officials insisted was untrue. (politico.com)